A few questions for chemistry 12?

Question

1) Silver chloride, AgCl, would be least soluble in
1.0 M AgNO3
1.0 M HCl
1.0 M NaNO3
1.0 M ZnCl2

2)The solute AgBr is least soluble in
1.0 M AgNo3
1.0 M FeBr3
H2O
1.0 M CaBr2

3)The concentration of Fe2+(aq) can be determined by a redox titration using
KMnO4 (basic)
SnCl2
KBrO3 (acidic)
KBr

Thanks for all the help in advance.

Answer 1

1. ZnCl2 - most Cl- ions.
2. FeBr3 - most Br- ions
3. KMnO4 acidic is the usual answer, but you can't do it in basic, so it must be KBrO3.